Universal behavior in the static and dynamic properties of the $α$-XY model

Andrea Giansanti, Daniele Moroni, Alessandro Campa

Published 2000-07-26, updated 2000-11-08Version 2

The $\alpha$-XY model generalizes, through the introduction of a power-law decaying potential, a well studied mean-field hamiltonian model with attractive long-range interactions. In the $\alpha$-model, the interaction between classical rotators on a lattice is gauged by the exponent $\alpha$ in the couplings decaying as $r^\alpha$, where $r$ are distances between sites. We review and comment here a few recent results on the static and dynamic properties of the $\alpha$-model. We discuss the appropriate $\alpha$ dependent rescalings that map the canonical thermodynamics of the $\alpha$-model into that of the mean field model. We also show that the chaotic properties of the model, studied as a function of $\alpha$ display an universal behaviour.